LoFP LoFP / false positives may be present and some filtering may be required.

Techniques

Sample rules

Windows COM Hijacking InprocServer32 Modification

Description

The following analytic detects the modification of the InProcServer32 registry key by reg.exe, indicative of potential COM hijacking. This detection leverages data from Endpoint Detection and Response (EDR) agents, focusing on process and command-line execution logs. COM hijacking is significant as it allows adversaries to insert malicious code that executes in place of legitimate software, providing a means for persistence. If confirmed malicious, this activity could enable attackers to execute arbitrary code, disrupt legitimate system components, and maintain long-term access to the compromised environment.

Detection logic


| tstats `security_content_summariesonly` count min(_time) as firstTime max(_time) as lastTime FROM datamodel=Endpoint.Processes
  WHERE `process_reg` Processes.process=*inprocserver32*
  BY Processes.action Processes.dest Processes.original_file_name
     Processes.parent_process Processes.parent_process_exec Processes.parent_process_guid
     Processes.parent_process_id Processes.parent_process_name Processes.parent_process_path
     Processes.process Processes.process_exec Processes.process_guid
     Processes.process_hash Processes.process_id Processes.process_integrity_level
     Processes.process_name Processes.process_path Processes.user
     Processes.user_id Processes.vendor_product

| `drop_dm_object_name(Processes)`

| `security_content_ctime(firstTime)`

| `security_content_ctime(lastTime)`

| `windows_com_hijacking_inprocserver32_modification_filter`